What's the benefit of Ceramic inserts?

Agreed, incredibly brittle, but they work better than anything else I've met on hard materials, e.g. bearing races - I'm hunting for ceramic inserts for the Horn grooving tool I have, to put a circlip groove in an outer race to make a replacement for an Unobtainium flanged bearing from the 50's - well, a bunch of them, the non-flanged are available (but not cheap), I'd have to order 500 of the flanged, at £600 each...

Dave H. (the other one)
 
BS I think you may have a hard time to find an insert with the proper dimensions for a circlip groove. You might want to look into an abrasive or a diamond wheel with a dremel or something similar somehow setup in the lathe. Going to be delicate and would need a perfect setup and patience.
 
The Horn grooving tool has its inserts on edge, there are HSS and carbide in my box down to 1.6mm, I know they do narrower but haven't yet found anywhere doing narrower in ceramic... ☹

The outer races are 2.250" diameter, so I think I can get up to the required surface speed for the inserts!

Dave H. (the other one)
 
That s what I meant with finding an insert in a ceramic in that dimension. You could shape an abrasive thin enough to give your width and plunge while the lathe is run at low speed. Once you use a dremel in this fashion you ll find more uses for it. Your depth isn t very much with the circlip groove so wouldn t have to thin out the whole wheel. Just your depth and a bit of clearance. I bet there is something close enough and you could plunge retract and move over and plunge again to give your width. Even your cheap dremel kits may have something that may work. Make something to hold the dremel in the toolpost yourself.
 
Hmmm... Sorry about the thread diversion!

Not a Dremelloid (though I have one, they're pretty low-powered), but I have a mount made to put my router (with base etc. detached) on the toolpost, an arbor for an angle-grinder 1mm cutting disc wouldn't be hard to make, I'd have to keep the RPM down though - fortunately it's variable speed enough to use with Scotchbrite wheels etc., so it should wind down enough... Keeping the flying debris off the lathe ways may take some doing though!

I've found the Horn catalogue on their site, though, and they do cermet inserts for my holder from 0.9mm upwards, might be cleaner than grinding :D
http://www.phorn.co.uk/fileadmin/us.../Carbide_Grooving_Tools_Chapters/312_S312.pdf

Dave H. (the other one)
 
Tony Wells said:
Cermet is a different animal.
Click to expand...
What he said.
Ceramic material in a metal matrix usually nickle, excellent tools in particular applications. It is used extensively in milling inserts and ran dry.
Not something a hobbyist would want to screw around with however as the cost may be somewhat prohibitive and the learning curve long.
 
Almost all I use is cermet inserts and I like them a lot...
 
Of course, the benefit of ceramics is high cutting speeds and better finishes: the faster a tool can be run, generally, the finer finish is created, and also very hard steels may be finished with accuracy. I tried cermet tools years ago, and was quite amazed at how durable they were, so much more than ceramic, however, the price was a bit much, so for the most part, we used carbide for nearly all work.
 
You must log in or register to reply here.
Back
Top